Process and apparatus for drying textiles



Dec. 14,- 1948' P. L. MILLER ET PROCESS AND APPARATUS FOR DRYING TEXTILES 2 Shets-Shee; 1

Filed Sept. 14, 1943 ATTORNEYS Dec. 14, 1948. P. L. MILLER ET AL 2,456,301

PROCESS AND APPARATUS FOR DRYING TEXTILES Filed Sept. 14, 1943 2 Sheets-Sheet 2 racemes p 4. r-

assessor PROGESS APPARAg'US F011; DRYING 'rms'rn. s

'1' lPaui manner and Fred "r.

Miliicr; Ciearwater,

S. 8., designers to lilnitedliflerchanto & Manutacturers, Ina, W of-Delaware win: lDel., a corporation Application cementeit, me, Serial No. 502,260

This invention relates In the textile industry, fabric is produced in large quantitlesin the form of elongated sheets 3 Claims. (oi. 34-418) to a method and apparatus for drying wet fabric.

of predetermined widths. It is subjected to various wet treatments suchas washing, bleaching. sizing, dyein etc, and it is highly desirable to provide means of drying which will be efiective and economical.

It is an object of thisinvention to provide an improved drying method and apparatus adapted for the practice thereof.

It is a further object to provide an improved method and apparatus which will" enable the A") -Fig. 31s a perspective view oi as'ource of radiant heat; Fig. 4 is a section on the line i-tl of Fig. 3;

Fig. 5 is a perspective view looking in the direction of 5-d of Fig. i and Fig. 6 is a partialsection entire line t ii of Fig.1.

In accordance with this invention, the fabric is first passed in closely spaced relation to a source of concentrated, preferably radiant heat the energy of which is sufficient to cause an instantaneous or flash volatilization of at least a substantial part of the water in the fabric. This source of heat may be a refractory body heated to incandescence or to flame temperatures by any suitable heating means which may be a flame.

The wet fabric is continuously passed at high speed in spaced relation to this body and is directly exposed to the radiant heat thereof and to the flame if flame is used as the source of heat. The direct exposureof the fabric to these high temperatures and concentrated heat sources is, however,-.only momentary so that although a substantial part of the water is evaporated, the fabric is not impaired.

Further according to the invention, the drying of the fabric is completed by a more prolonged exposure of the fabric to heated gases or vapors for example hot combustion gases which may be mixed with steam. Where such mixture is employed, the invention preferably employs the steam generated by volatilizationof the water from the fabric by the herein above described momentary direct exposure to the source of concentrated heat.

' The principles of the invention will be'deflned in the claims and one of the various embodiments of those'prlnciples will be described by reference to the accompanying drawings in which 4 Fig. 1' is a diagrammatic view showing the drying apparatus in elevation taken on line l-i of Fig. 2.;

Fig. 2 is a horizontal diagrammatic sectional view on the line 2-.2 or Fig. 1;

The apparatus specifically shown comprises a generally rectangular body having vertical side Walls 8'', vertical and walls 2 and 2A, a top ii and bottom it. A partition d separates the chamber into what may be termed a flame chamber or radiant heat chamber d and a convection heat chamber, including the chambers It, ii and passageways 2d. The wall 2A terminates in a horizontal wall 213 provided with a door 5 pivoted to swing about an axis coincident with the intersection of the planes of walls 23 and 8A. the latter being substantially aligned with the wall ii. The function of the door will be later described.

In the chamber 9 groups l2, it of heating elements it are mounted on brackets-it secured to the wall 2A, each of these groups l2, l3 consisting of heating elements supported one above the other. One of the heating elements is shown in perspective view in Fig. 3 and in sectional view in Fig. 4. As there shown, the heating element designated generally as i6 is made up of a series of refractory U-shaped blocks i1 arranged side by side and provided with a backing member It. A manifold 20 for fuel gas extends within and longitudinally of the backing member it to which manifold nozzles M are connected, there being conveniently one nozzle for each block W. The orifices 0f the nozzles ii are directed downwardly..tha.t is, substantially perpendicular to the iongitudinal axis of the U-shaped depression in the heating element It so that the flame delivered by the nozzles impinges on a curved surface of the blocks and is then directed outwardly. It will be understood that a mixture of air and fuel gas may be delivered through the manifold 20 or this manifold may merely carry fuel gas and be mixed with air at each individual nozzle. Details as to the specific burner structure are not needed since they may readily be supplied in accordance with the knowledge of the burner art.

Between the chambers ill and ii, there are a series of serpentinepassageways 23 defined by a series of spaced V-shaped walls 26 and 25, constituting a drying tunnel. The upper series of walls It partly define the chamber H and the lower series of walls 25 partly define the chamber I 0 also partly defined by the horizontal partition 30. Delivery ducts 32 leading from blowers i 23 are arranged to deliver hot combustion gases from the blowers 33 to the undersides of the walls 25. The impellers 54 of the blowers 33 are mounted on shafts 36 rotated by pulleys 3T driven by belts 38 from motor 39 as shown in Fig. 2. Each blower 83 is provided with an intake duct I to which hotcombustion gases are delivered by burners 42 (note Fig. 2). Each duct I is provided with an auxiliary or branch duct 43 carrying acontrol damper 44 for purpose of control of recirculation of hot combustion gases.

Partition III extends part way across the convection chamber I I adjacent the top 3 thereof and is secured to side walls IA (note Fig. 6) positioned in spaced relation to wall I. This partition I terminates in spaced relation to walls 8 and 2 respectively and, with top'! defines a space 55 communicating at one end with a space 6513 and at the other end with space 55A. The space II is defined by wall 8 and a vertical wall I2 joined to the partition III and to one of the walls 2|. The walls I2 and I3 extend transversely of chambers II and II and are secured to side walls IA. The space 65A is defined, in part. by wall 2 and a vertical wall I8 which is joined to one of the walls and to the partition The latter terminates in spaced relation to walls 2 and 8A, respectively, and is joined to side walls IA. It will be seen therefore that the walls I0, 38, I2, I3 and IA, defining the convection chambers III and II, are in spaced relation to the end walls 2 and 8, the side walls I and the top and bottom walls 3 and 4 constituting the outside shell of the apparatus (exclusive of the radiant chamber 9) and that between this outside shell and the walls defining chambers I0 and II there is clearance at the top. bottom, sides and both ends. Delivery ducts 32 are connected to openings in partition 30. At the top of space 65A and adjacent one end of space 85, a vent 13A carrying control damper I4 is provided.

A duct 46 leads from the space 9 to the intake 41 of a blower 48, the discharge duct 5|! of which passes through walls 3 and I5 and discharges into the chamber II. The duct 45 communicates with space 65 through pipe .5I- carrying control damper 52.

Guide rollers 51 are provided and suitably mounted in journals 51A secured to side walls IA to conduct the fabric 58 from an accumulation thereof through opening 54 in wall 2A, first in spaced relation to the groups I2, I3 of heating elements I6 and then through the serpentine passageways 23 and in spaced relation to the (walls 24, 25 which define those passageways (said walls being provided with slots 65; note Figs. 5 and 6) and between a pair of rolls 5| which pull the fabric I through the apparatus and deliver it to an accumulation 63 in a storage bin Ill.

In practicing the method of the invention and using the illustrated apparatus, the fabric 58 continually passes downwardly in the chamber 9 in spaced relation to the groups I2, I3 of heating elements I6, the door 5 being in the closed position shown in full lines. These elements are preferably made of refractory material and may be heated to flame temperatures or incandescence by electrical resistance elements or, as specifically shown, by a flame of burning fuel gas. When using the specific heating elements shown herein, the flame will be directed outwardly from the 'U-shaped depression in the elements as a sheet of flame substantially perpendicular to the plane of the downwardly passing fabric. The latter passes in closely spaced relation to the heatin elements and is directly exposed to the radiant heat thereof and also to the flame and the flame may actually impinge on the fabric. However, the speed of travel of the fabric is such that the exposure to these drastic heating conditions is only momentary and therefore the fabric is not in any. way impaired since the latter never reaches the temperature of carbonization or incineration, the heat energy reaching the fabric being absorbed in volatilizing a substantial part of the water in the fabric. This water in the form of superheated steam is delivered by the intake duct 46, blower and discharge duct 5|! to what may be termed the convection heating chamber I I and delivered downwardly to the walls 24 by the blower 45. At the same time, hot combustion gases are delivered upwardly against the walls 25 by blowers 28 through ducts 32. The steam and hot gases, respectively, enter the serpentine passageways through elongated slots while the fabric is passing through those passageways and effect completion of the drying of the fabric which is already partly dried in the radiant chamber 8.

Ample opportunity is provided for recirculation of the mixture of steam and hot combustion gases delivered to the serpentine passageways and discharged into the space A. The mixture may pass to the space 65 and down into space 553, then into space 9 and back to chamber II via the blower 48. If damper 52 is open or partly open. the mixture may pass through space 85, duct 5| and then to chamber I I via blower 18. If dampers 44 in ducts 43 are open or partly open, the mixture may pass down to space 65 between partition 30 and bottom 4 and then to walls 25 via blowers 33. The mixture may also pass through the spaces I5, between walls I and IA (note Fig. 6), then to space 9 and back to chamber II via blower 48. The mixture may be vented through vent 13A. The proportions of the mixture distributed through these various paths may be controlled by dampers 52 and I4.

When the apparatus is shut down, the door 5 is opened, i. e., placed in the position indicated by dotted lines in Fig. 1. Continued operation of the blower 48 then draws cold air from the outside through space 9 and hot gases from chambers II. II and 65 are excluded. This precaution prevents burning of the fabric by residual radiation from elements I6.

-While the exposure of the fabric to the drastic heating conditions described in connection with chamber 9 is only momentary, the exposure to the milder heating conditions in chambers III and II is more prolonged, as will'be readily seen, so that by the time the fabric leaves the apparatus through the opening 66, it is in substantially dry condition for delivery to the storage bin 64.

We claim:

1. The process of drying wet fabric which comprises continuously passing said fabric through a flame chamber in closely juxtaposed and spaced relation to an incandescent refractory body; directly exposing the fabric to said body for a time sufficient to volatilize a substantial proportion of water from said fabric and convert it into steam;

mixing said steam with hot combustion gases, passing the fabric through a convection heat chamber, introducing said mixture of steam and combustion gases to said convection heat cham-- her from opposite sides thereof andin direct heat exchange relation with said fabric in order to complete the drying of the fabric, and recirculating said mixture through said convection'heat chamber only in contact with said fabric.

2. Apparatus for continuously drying wet fabric comprising an enclosed'chamber, means to pass fabric in elongated sheet form through said chamber, means in one part of said chamber providing a flame-heated source of radiant heat: a series 01' interconnected serpentine passageways in another part of said chamber, said passageways being defined in part by parallel walls in spaced relation, said walls having slots therein, means to continuously pass said fabric at high speed first in closely spaced relation to said source of radiant heat to volatilize a substantial part of the water in said fabric without injuring it and then through said serpentine passageways to complete the drying of said fabric; means to generate combustion gases and to circulate the same through said slots; and means to mix with said combustion gases steam evolved by exposure of said fabric to said source of radiant heat.

3. Apparatus for continuously drying wet fabric comprising an enclosed chamber, means to pass fabric in elongated sheet form through said chamber, including a series of widely spaced upper and lower rollers in said chamber adapted to support the fabric in a multiplicity of substantially vertically extending stretches intermediate the rollers, partition means separating oil. a lim-- ited section of said chamber at the entrance end thereof to accommodate a short length only 0 the total length of fabric supported within the chamber, a source of radiant heat in said section located adjacent the said fabric, means to circulate steam drawn from said limited section through the remainder of the chamber, and means to introduce combustion gases to the remainder or said chamber in a direction opposite to the introduction of the steam.

PAULLMILLER. FREDQMIILER.

6 assurances crrnn The following references are of record in the ille of this patent:

UNITED STATES PATENTS Number Name Date 1,280,570 Pease Mar. 26, 1918 1,476,362 Glennie Dec. 4, 1923 1,571,282 Leculier Feb. 2, 1926 1,676,092 Kemp July 3, 1928 1,686,597 Bock Oct. 9, 1928 1,996,020 Hurxthal Mar, 26, 1935 2,024,079 Whiting Dec. 10, 1935 2,050,977 Smith et al Aug. 11, 1936 2,099,160 Church Nov. 16, 1937- 2,101,301 Wellmar Dec. 7, 1937 2,127,956 Helmet Aug. 23, 1938 2,186,032 Mann Jan. 9, 1940 2,220,928 Kienle Nov, 12,- 1940 2,225,166 Erby Dec. 17, 1940 2,313,173 Schneider Mar. 9, 1943 2,384,990 French Sept. 18, 1945 OTHER REFERENCES "Use of Infra Red-Ray Gas Burners in the Textile Industry," Rayon Textile Monthly, June 1942, p. 62.

Clarifying Radiant Heat Applications in Textile Finishing," Van Kompen in Rayon Textile Monthly, Aug. 1943. pp. 75-76.

"Scientifically Applied Radiant Heat in the Textile Industry," Weiss in Rayon Textile Month- 1y. Sept. 1943, pp. 127-129. 

